Apparatus for preventing collisions on electric railways



v(No Model.) 4 Sheets-Sheet 1.

B. o. TILGHMAN, Jr. APPARATUS POR PRBVENTING COLLISIONS ON ELECTRICRAILWAYS.

No. 573,496. 1 Patented Deo. 22, V1896.

(No'uodel.) 4 'sheetssheet 2'.' B. C. TILGHMAN, J1.

APPARATUS POR PRBVBNTING GOLLISIONS 0N BLBGTRIG RAILWAYS.

Patented Dec. 22, 1896.

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(No Model.) 4 Sheets-Sheet -3.

B. C. TILGHMAN', Jr.

APPARATUS FOR PRBVBNTING GOLLISIONS 0N ELECTRIC RAILWAYS.

(No Model.) 4 sheets-snm 4.

B. o. TILGHMAN, Jr. APPARATUS FOR PRBVBNTING GOLLISoNS 0N ELECTRICRAILWAYS.

Patented Deo'. 22, 1896.

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UNITED STATES PATENT OFFICE.

BENJAMIN C. TILGHMAN, JR., -OF PHILADELPHIA, PENNSYLVANIA.

APPARATUS FOR PREVENTING COLLISIONS 0N ELECTRIC RAILWAYS.

SPECIFICATION forming part of Letters Patent No. 573,496, dated December22, 1896.

Application filed April 13, 1894. Serial No. 507,367. (No model.)

Be it known that I, BENJAMIN C. TILGHMAN, .I r., a citizen of the UnitedStates, residing in the city of Philadelphia, in the county ofPhiladelphia, in the State of Pennsylvania, have invented a new anduseful Improvement in Apparatus for Preventing Collisions on ElectricRailways, of which the following is avtrue and exact description,reference being had to the accompanying drawings, which 1 orm a partthereof.

My invention relates to apparatus for preventing -collisions onelectrically-actuated railways, and has for its objects, first, toprevent collisions, particularly where one road crosses or meetsanother, and also to prevent collisions on the same road; also, toprovide a suitable signal when a car is on a portion of the road where acollision might occur, and also to provide an alarm on and to check thespeed of the car which has not the right of way. To accomplish theseobjects, I provide insulated feed-sections on the crossing roads,extending for suitable distances on each side of the place of crossing,and provide means for cutting off the current on the section of one roadwhen a car is on the corresponding section of the other, and I alsoprefer to ground the section from which the current is cut off andoperate an alarm by means of a current which passes, preferably, througha high-resistance connection from the live to the grounded section. Ialso provide an improved connection in block-sections on the same road,whereby an improved operation is obtained with much less wiring.

My improvements will be best understood as explained in connection withthe accompanying drawings, in which- Figure l is a side view of acut-out instrument which can conveniently be employed to open and closethe circuits in the desired manner. Fig. 2 is a plan View of a polarizedrelay adapted to operate an electric bell. Fig. 3 is a diagrammatic viewshowing the wiring of two single-track roads which cross each other.Fig. 4 is a similar View showing the wiring of two meeting roads. Fig. 5is a diagrammatic View showing the wiring of two double-track roadswhich cross each other.

tem arranged according to myinvention and applied to a trolley-road; andFig. 7 is a view similar to that shown in Fig. 6, but showing amodification.

Referring tirst to Fig. 3, A B are two crossing roads, the cars on whichrun in the direction indicatedl by the arrows. Each of the roads isshown provided with an insulated sectional feed-supply conductor ct Z2,extending back from the crossing-point for any desired distance,insulation being provided at 1', as shown.

F G are feed-conductors (shown as heavy solid lines) for the roads A B,respectively, and are normally connected to the insulated sections bymeans of circuits fj and g g', respectively. I provide means, however,for opening either of these connecting-circuits when a car is takingcurrent from the sectional feed-conductor to which thatconnectingcircuit does not lead. A convenient apparatus for doing thisis shown in Fig. l.

The essential features of this apparatus are magnets, as D K, the coilsof which are energized by or form part of the two circuits leading fromthe feed-conductors to the sectional power-supply conductors and meansoperated by each of said magnets when energized for opening the circuitwhich operates the other. As shown, the circuits f g pass around similarcores D K', thus forming electromagnets D K, and pass from there tocontact-plates D2 K2. Armature-levers E L, which are substantiallysimilar and only referred to by dierent reference-letters for purposesof identification, are pivoted at e Z, respectively, and are providedwith armatures E' L'. Contact-points e2 Z2 engage with the contacts D2K2 and form part of the circuits ff/ g g", the connections f g', leadingto the insulated sections CL Z), be-

ing shown connected to the lever-arms e' Z', on which said contacts e2Z2 are situated. Positively-actuated non-magnetic means, as a Vweight orspring, as indicated at E2 L2, serve to hold the'contact-points e2 D2and Z2 K2 normally in engagement. These positively-actuating means arearranged to operate with different force on the levers for a purpose tobe hereinafter explained. As shown, the weight at L2 is placed fartherout on its arm than the weight E on its arm, so as to actwith differentforce than said weight. I also prefer to ground the section ct or b fromwhich the current has.

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' of crossing each other.

been cut oft', and, as shown, contacts e3 Z3 are adapted to be engagedwith contacts J J2 of the ground-wire .I by the same movement that disengages the said section from its feed-wire. In operation it will be notedthat if a current passes through the circuit ff and around the magnet Dthe armature L will be operated and the lever L so turned on its pivot lthat the contact Z2 K2 will be broken, thus opening the circuit g g',while contact of Z3 J 3 will be made, grounding the conductor connectedto the line g.

S is a signal of anyl desired form which is adapted to be operated ordisplayed when one section is grounded and the other section inconnection with the feed-conductor. A circuit s t, preferably of veryhigh resistance, so that any current which passes will not b esufficient to operate a car-motor, connects the two sections a b, andso,when one section is grounded, a current passes through this circuitfrom the live to the grounded section,'thus operating the signal. Itwill be noted that the signal will not be operated between two dead orbetween two live sections having the same voltage. The signal S is ofcourse so placed that it can be clearly seen from both roads.

The arrangement shown in Fig. 4 is suhstantially the same as that shownin Fig. 3, the two roads A2 and B2 meeting at XV instead Part-s similarto those shown in Fig. 3 are indicated by the same reference-letter withthe index 2 added.

In Fig. 5 a double-track road A4 A5 crosses another double-track roadI34 15"", the cars thereon traveling in the directions indicated by thearrows. The insulated sections a4 a5 are shown fed from the samefeed-wire F4A and the insulated sections b4 b5 from a feedwire G4. Acaron one of the sections a4 a5 will cut off the current from and groundthe other sections b* b5 and set the signal S in the manner beforedescribed7 a car on the sections Zfl b5 acting in the same way as to thesections a4 a5. I also preferably provide an alarm on the cars, soarranged that if any car attempts while running to take power from acut-out and grounded section a local alarm will be given on that car.Such an alarm is shown in Fig. 2, and consists of an electric bell N,operated by magnets N. In the circuit of these magnets N' arecontact-points controlled by an apparatus in the nature of a polarizedrelay. This relay conveniently consists of a permanent magnet M,pivoted, as shown, between the poles of the magnets H II'. lVhen thecurrent passes in one direction through these magnets, the permanentmagnet is attracted and breaks the alarm-circuit. This is the conditionwhen the current is passing normallyfroin the power-supply conductor tothe motor, the alarm and magnetic circuits around the magnets I-I IIbeing arranged as shunts upon thel rheostat controlling the speed of thecar. If now the car runs onto a grounded insulated sectional lconductorand y attempts to take power from said conductor,

it is evident that there will be acounter electromotive force generatedby the motor, which of course is moving with the car, and this will notonly act to brake the car, but will also send a current through themagnets II H in an opposite direction to that previously directedthrough them. The polarity of these magnets will be reversed and themagnet-armature M will be repelled, assuming the position shown in Fig.2, closing the alarm-circuit and ringing the bell or operating any otheralarm for the information of the motorman, who can then easily stop thecar. In this connection it will be noted that when a vehicle is on oneof the danger-sections of one road it not only cuts out but also groundsanother section through the wire J. (See Fig. l.) This of course makes aground for the moto-1*,-connected to the cut-out section by way of thetrolley-arm, and permits the counter electromotive force of the motor toactuate the bell.

In cases where one road always has the right of way it will of course bepracticable to provide but one insulated section and cut it out by theaction of a car on the dominant road.

It will be noted that if two cars arrive on the insulated sections atexactly the same instant both will first momentarily receive' current.This will result in both cuttin g out the other. Both being cut out, themagnets will be cenergized and the armatures free to move into theposition shown in Fig. l under the influence of the weights E L2 orother operating mechanism. One of these mechanisms, however, operates,as has been said,with greater force than its neighbor, and therefore itsarmature will iirst close the circuit which it governs, and which,operating the magnet which it surrounds, will immediately andpermanently cut out the other section, the car whose circuit is tirstyclosed having, therefore, the right of way. Substantially the sameprinciple can be employed to prevent collision on a single-track road,and by my arrange- IOO IIO

ment I save a great deal of the wiring which i is necessary in settingup prior systems to accomplish the same purpose. I also provide an alarmwhich will indicate to any one entering on a block whether there is anycar on the next block.

In Fig. 6 I have indicated in diagram an arrangement for preventingcollisions on the same road. p/ p2, the., are insulated sectionalfeed-conductors; F6, a feedwire; r' r2, connections from the feed-wireto the di'erent sections p p2, dac. K is a magnet having a coreK exactlysimilar to the magnet shown in Fig. l. weight or spring L2 adapted tokeep the armature-lever L in the position, as shown, above the vehicleV, soV as to connect a section, as

p2, with the feed-wire through the connection r2. connection r2, itenergize's the magnet K, as shown at the left of said figure, andconnects Lis an armature-lever having a When a current is passingthrough this the said section to earth through the groundwire j. Afterthe vehicle V has passed from the section p the weight or othermechanism L2 moves the armature to put the said section in connectionwith its feed-wire. I also prefer to arrange an alarm S between thesections,which alarm will operate when a current passes from one sectionto another, as when the preceding section is grounded.

In Fig. 7 the construction is substantially the same, except that theground-wires are omitted. In this case the alarm S will not be operateduntil a car comes on the insulated section, which will then be groundedthrough the motor-circuit and the alarm will be operated. Thisarrangement of an alarm between two sections, one of which may beprovided with a current in excess of the other and so that the alarmwill be given if the relative amount of currents on the two sectionsvaries, enables me to dispense with considerable wiring and makes thealarm perfectly automatic. The operation is believed to be perfectlyunderstood. If a car runs on an insulated section, it immediately cuts othe current from the section on the crossing road, grounds said section,and sets the alarm. A car subsequently attempting to obtain power fromsaid cut-out section is not only deprived of power, but a braking actionis set up by the counter electromotive force of the motor, and a localalarm is operated. In the case of the block-sections the same thinghappens if a car runs on a cut-out section, preferably the sectionimmediately preceding the one on which the iirst car is running.

In a road composed of a number of insulated sections or blocks providedwith the cut-out apparatus, as above described, it is evident thatshould a car or other vehicle running on any given block break down orbe there stopped by some cause which prevents it from taking currentfrom its section in this case the cut-out section in the rear of thatupon which the car was traveling would then be restored to the circuit,and thus the safeguard provided be withdrawn at just the time that itwas needed. To prevent this action, I provide a circuit around the motoron the car or vehicle traveling on the said road of such suitableresistance and so controlled by a suitable and convenient switch thatwhen the same is closed there will be drawn through the said circuitfrom the section upon which the car has stopped a sufficient amount ofcurrent to maintain the section in the rear of the said car cut out fromthe source of electric supply. Such an apparatus is indicated in Figs. 6and 7, where c5 is a suitable conductor, preferably of considerableresistance, which is adapted when the switch c4 is closed to permit sucha flow of current around the motor that the previous section or desiredsection will remain cut out.

It will of course be noted that when I referv to grounding7 a wire Imean connecting it to the other side of the circuit or to the other poleof the electric generator. This, while usually the ground, may of coursebe a metallic return-conductor.

The section and feed conductors may of course be the ordinaryarrangement of trolley and feed wires or any other manner ofinstallations by which cars or vehicles of any sort are driven byelectrical energy supplied from outside the car or vehicle, and while Iprefer to operate the vehicles by a unidirectional current it is ofcourse evident that by properly laminating the cores of theelectromagnets D K and designing the helices so as not to have anobjectionable self-indirection the apparatus shown in Fig. 1 can beoperated with an alternating current in the same way as with oneconstant in direction. Indeed everything but the local car-alarm willoperate in exactly the same way with alternating as with unidirectionalcurrents.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. The combination with the crossing tracks and an electric conductorextending along one track for supplying electricity as a motive power,of means under the control of a train moving along the other track fortemporarily cutting the electricity off from a portion of said conductoralong the first-named track.

2. The combination with two electricallyoperated roads which meet'orcross each other, of a source of electrical supply, an insulatedsectional conductor connected to said source of electrical supply andadapted to furnish power to a vehicle traveling on a portion of oneroad, and means operated by one vehicle traveling on a predeterminedportion of the other road for cutting off the current from the insulatedconductor of the first road.

3. The combination with two electricallyoperated roads which meet orcross each other, of a source or sources of electrical supply, twoinsulated sectional conductors, each connected to a source of electricalsupply and adapted, one to furnish power to a vehicle traveling on aportion of one road, and the other to furnish power to a vehicletraveling on a portion of the other and means operated by a vehiclereceiving power from either of the insulated sections for cutting oifthe current flowing to the other section.

4. The combination with two electricallyoperated roads which meet orcross each other, of a source or sources of electrical supply, twoinsulated sectional conductors, each connected to a source of electricalsupply and each adapted to furnish power to a vehicle traveling on aportion of one road and means operated by a vehicle receiving power fromeither section al conductor for setting an alarm as S.

5. The combination with two electricallyoperated roads which meet orcross each other, of a source or sources of electrical supply, twoinsulated sectional conductors, each connected to a source of electricalsupply and IOO IIO

each adapted to furnish power to a vehicle traveling on a portion of oneroad and means operated by a Vehicle receiving power from either of theinsulated sectional conductors for cutting out the circuit from theother section and simultaneously setting an alarm as S.

G. In an electric railway the combination with a number of sectionalpower-supply conductors, of a feed-conductor, connections between thefeed-conductor and the sectional conductors, a circuit-controller forgoverning said connection, positive-acting non-magnetic means fornormally holding said connections closed, and means operated by thepassage of a current from the feed-conductor to one sectional conductorfor operating the circuit-controller so as to open the circuit leadingto another section whereby rear-end collisions can be prevented.

7. In an electric railway the combination with a number ofsectional'power-supply conductors of a feed-conductor normally-closedconnections between the feed-conductor and the sectional conductors,circuit-.controllers consisting of electromagnets the coils of whichform part of the connections between the feed-conductor and thesectional power-supply conductor, and armatures operated by eachelectromagnet tor opening a connection leading` to another section so asto, prevent collisions.

S. In an electrically-actuated road, a sectional power-supply conductor,a feed-conductor normally connected to said sectional conductor, a motoradapted to receive power from said sectional conductor, an alarm in themotor-circuit adapted to remain inoperative during the normal flow ofthe current and means for cutting out the sectional conductor andgrounding it whereby a reverse current will be set up and the alarmoperated by the counter electromotive force of the motor while it is inmotion.

9. The combination with two electricallyoperated roads which meet orcross each other, a source or sources of electrical supply, twoinsulated sectional conductors, each connected to, a source ofelectrical supply and adapted one to furnish power to a vehicletraveling on a portion of one road and the other to furnish power to avehicle traveling on a portion of the other, and means operated by avehicle receiving power from either of the insulated sections forcutting off the current flowing to the other section, and grounding thatsection.

l0. The combination with two independent circuits, of electromagnets DK, each forming part of one of said circuits, an armature actuated byeach magnet and serving to open the circuit passing around the othermagnet and positively-actuated means for closing the circuits after thecurrent which operated to open them has ceased flowing, said meansacting with diierent force so that if both circuits were openedsimultaneously one will be closed before the other.

ll. The combination with two electricallyactu ated roads which meet orcross each other, of a feed conductor or conductors, sectionalpower-supply conductors, each adapted to supply energy to a vehicle ondifferent roads, connections leading from a feed conductor orconductors'to each of the sectional conductors, a magnet forming partot' each of these connections and an armature operated by each magnetand adapted when operated to open the circuit of which the coils of theother magnet form a part.

l2. The combination in an electrically-actuated railway of a number ofinsulated sectional power-supply conductors arranged one behind theother, a feed-conductor normally connected to each sectional conductor,an

alarm arranged in a high-resistance circuit which connects thelotherwise-insulated seetional conductors, means operated by a vehicle onone section for cutting out another section whereby a current will passto the cutout section from the adjoining sections if said section begrounded and operate the alarm.

13. The combination in an electrically-actuated railway of a number otinsulated sectional power-supply conductors arranged one behind theother, a feed-conductor.normally connected to each sectional conductor,an alarm arranged in a high-resistance circuit which connects theotherwise-insulated sectional conductors, means opera-ted by a vehicleon one section for cutting out and grounding another section whereby acurrent will pass to the cut-out section from the adjoining sections andoperate the alarm.

14. The combination with two independent circuit-magnets D K one in eachcircuit, a ground-wire J, two armatures, one operated by each magnet andcontact-points on each armature so arranged that when an armature isoperated by its magnet it breaks the circuit around the other magnet andconnects said circuit tothe ground-wire.

l5. The combination with two independent circuits of magnets D K, one ineach circuit, two armatures, one operated by each magnet and eachprovided with contact-,points normally forming part of the circuitaround the other magnet and positively-acting means for holding thearmatures away from the magnets.

16. rIhe combination with two independent circuits, of magnets D K onein each circuit, two armatures, one operated by each magnet and eachprovided with contact-points normally forming part of the circuit aroundthe other magnet and positively-acting means acting with different forceon each armature for holding said armatures away from the magnets.

17. The combination in an electrically-actuated railway of a number ofsectional powersupply conductors arranged one behind the other, afeed-conductor normally connected to each sectional conductor,positively-actin g IOO IIC

non-magnetic means for normally holding cut-out section may be kept cutout as long said feed-conductors in circuit with each secas necessary.

tional conductor, ineens operated by a Vehicle While it is receivingenergy from one section BENJAMIN C' TILGHMAN JR" for cutting ont anothersection, and a con- Vitnesses: ductor for permitting` a flow of currentwhen ROBERT lV. LLOYD, the motor is cut out or disabled whereby the f D.STEWART.

